<!DOCTYPE html>
<html lang="en">

<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
</head>

<body>
    <div id="app">
        <div>
            <div style="display: inline-block" v-for="(item,index) in arr">
                <input type="checkbox" :value="item" v-model="num" />
                <span>{{item}}</span>
            </div>
            <p>你选中的元素, 累加的值和为: {{he()}}</p>
        </div>
    </div>
    <script src="./vue.js"></script>
    <script>
        const app = new Vue({
            el: '#app',
            data: {
                arr: [9, 15, 19, 25, 29, 31, 48, 57, 62, 79, 87],
                num: []
            },
            methods: {
                he() {
                    const bb = this.num.reduce((a, b) => a + b, 0)
                    return bb
                }
            }
        })
    </script>
</body>

</html>